Before wireless high frequency point-to-point communication service can be provided on a mass basis in an area there must exist a deployment scheme that can support the planned service. Such a scheme must be able to deploy a large number of radio links, i.e., two way radio communication established through main beams of both transmitting and receiving antennas where the antenna gain is at its maximum in a given area such that the individual radio links do not significantly interfere with one another.
There are a number of parameters that determine the magnitude of such interference, such as the antenna gain in the path of the interference, the "hop" distance between interfering and interfered, polarization isolation and frequency channel separation. For example, interference is worst case where the interfering transmitting main beam is directed towards the interfered receiving main beam, somewhat less when the interfering main beam is directed toward the interfered receiving sidelobe, and even less when the interfering transmitting sidelobe is directed toward the interfered receiving sidelobe. Additionally, the interference decreases the farther apart, i.e., the greater the "hop" distance between the interfering and the interfered. Likewise, orthogonal polarization and frequency separation provide radiation in transmitting to receiving interference.
A good example of a deployment scheme is the cell structure currently in use for cellular wireless service. The cellular cell structure provides a model to show that the interference is controllable by frequency reuse and sectorization. Typically, in a cellular network, each set of frequencies is reused in every seventh cell, with each cell divided into three sectors.
Cellular networks are broadcast based such that a transmitter sends out signals into a designated area and any receiver within that area can pick up the signals, if properly tuned. Point-to-point radios work at a frequency, typically above 18 GHZ, where the wavelengths are short so that for effective communication the transmitter and receiver must be pointing essentially directly at each other, i.e., line of site. Such narrow beam transmission implies that the transmitters and receivers are all in fixed positions with respect to each other where their density is not great. Thus, in contrast to cellular systems, there is no need in point-to-point systems to "blanket" a given area with transmitted signals. This line of sight requirement has allowed point-to-point systems to be constructed without regard to each other. However, as the demand for point-to-point systems increases (because of their inherent higher data carrying capacity), interference between discrete systems will result when a particular receiver is within the radiation pattern of more than one transmitter.
Thus, a need exists in the art for a system and method for developing a deployment pattern for transmitter/receiver pairs so as to minimize interference while maximizing the frequency reuse pattern.
A further need exists for such a deployment system which can be replicated from location to location.
A further need exists for such a system in which not all of the transmitter/receiver pairs need be deployed at any time, but which will accommodate growth in any direction throughout the deployment region on a pre-approved basis.
A need exists for a deployment standard for high frequency radio transmission systems which will allow any transmitter/receiver pair to be added by any user at certain calculable points within a geographic region while still maintaining maximum effective coverage within that region.